Electrical switch



Oct. 6, 1953 Filed June ll, 1948 R. A. GESELLSCHAP ELECTRICAL SWITCH 3Sheets-Sheet 1 ROBERT A. GlisELLsczd/u4 ATTORNEY Oct. 6, 1953 R. A.GESELLSCHAP 2,654,814

ELECTRICAL SWITCH Filed June'll, 1948 3 Sheets-Sheet 2 /f /09 l I,

y INVENTOR ROBERT A. GEsELLscHAP ATTORNEY Oct. 6, 1953 Filed June ll,1948 FIG. 4

FIG. 3

R. A. GESELLSCHAP ELECTRICAL SWITCH 5 Sheets-Sheet 3 INVENTOR ROBERT A.GESELLSCHAP BY M ATTORNEY Patented Oct. 6, 1953 ELECTRICAL SWITCH RobertA. Gesellschap, Kirkwood, Mo., assignor to James R. Kearney Corporation,St. Louis, Mo., a corporation of Missouri Application J une 11, 1948,Serial No. 32,465

Claims.

This invention relates generally to electrical switches and morespecically to a reclosing switch structure which is adapted for use inmaintaining service of electrical energy from feeder circuits to animportant user of electrical energy, a hospital, for instance, thepredominant object of the invention being to provide a reclosing switchstructure, adapted for the use referred to above, which is of suchimproved construction and arrangement that it is capable of performingits intended function in an improved and highly efficient manner.

In the case of an important user of electrical energy where failure ofelectrical service would create a serious emergency, such, for instance,as a hospital, it has been the practice heretofore to provide such auser with two feeder circuits, one of said circuits being the preferredcircuit which normally feeds electrical energy to the user, and theother circuit being an emergency circuit which is placed in service onlyin the event a failure occurs with respect to the preferred circuit. Itis highly essential, in the event of a failure on the preferred feedercircuit of such an important user, that the switch-over to the emergencycircuit be made instantaneously so as to avoid even slight interruptionof service of electrical energy to the user.

The reclosing switch structure of the present invention is soconstructed and arranged, and is capable of such use, that immediatelyon failure of service to the user over the preferred circuit aswitch-over to the emergency circuit is automatically made in a fractionof a second so that there is practically no interruption of service ofelectrical energy to the user. In addition to the foregoing, theimproved switch structure of the present invention includes fusiblemeans which affords protection against cla-mage resulting from overioadsand short-circuits occurring on either the preferred circuit or theemergency circuit, depending on which of said circuits is in service atthe time the fault occurs.

Fig. l is a front elevation of the improved switch structure of thepresent invention.

Fig. 2 is a fragmentary, side elevation of the improved switch structureof this invention with parts broken away to permit of the structurebeing drawn to a larger scale than would otherwise be possible.

Fig. 3 is an enlarged, fragmentary, vertical section of an upper portionof the improved switch structure taken on line 3 3 of Fig. l.

Fig. 4 is a section taken on line 4-4 of Fig. 3.

Fig. 5 is a vertical section taken on line 5-5 of Fig. 3.

(Cl. 20G-126) Fig. 6 is an enlarged vertical section taken on line 6 6of Fig. 1.

In the drawings, wherein is shown for purposes of illustration, merely,one embodiment of the invention, A designates the improved switchstructure generally. The switch structure A includes a pair ofinsulators I and 2 which preferably though not necessarily, are disposedvertically, said insulators being spaced apart in a horizontal directionas is shown to good advantage in Fig. l. The insulators I and 2 areembraced respectively by suitable brackets 3 and 4, and these bracketsare secured to an elongated, horizontally disposed channel member 5adjacent to the opposite ends of said channel member, said channelmember being secured at its approximate longitudinal center to aclamping structure 6 which clampingly engages a cross arm, or othersupport S, for supporting the switch structure in position for use. Thelower portions of the insulators I and 2 have secured thereto saddlemembers 'I and 8 and fixed to these saddle members is an elongated,horizontally disposed bar 9 which serves as a bus terminal and extendsfrom one to the other of said insulators I and 2.

The bar 9 is secured adjacent to its opposite ends to the saddle members'I and 8 by bolts I0 and II, the bolt I0 serving also to secure to thebar 9 and the saddle member l of the insulator I, a supporting member I2which provides support for a fuse cartridge Ca. The cartridge supportingmember I2 includes an upstanding ilange I2a through which the shankportion of the bolt IG ext-ends, and said cartridge supporting member isprovided with a head portion I 2b which is shaped as is shown to goodadvantage in Fig. 6 and is provided with trunnions I3 which extendoutwardly in opposite directions from the opposite side faces of saidhead portion. Preferably the head portion of the cartridge supportingmember I2 is provided with arcuate centering flanges I 2c which extendoutwardly from the opposite side faces thereof.

The fuse cartridge Ca is of the expulsion type and comprises an openended tube I4 formed of electrical insulating material. The tube I4 ispreferably of composite construction, embodying an inner tubular portionI4a of horn fiber, and outer tubular jacketing portion I 4b of Bakelite,or other insulating material having equivalent weather-resistingproperties. It'has been found advantageous to employ horn ber in theconstruction of the tube I4 of the cartridge Ca because of the fact thatsuch material is characterized by the ability to give off gas in thepresence of the heat of an electric arc which tends d to extinguish thearc. The tube I4 of the fuse cartridge has iixed thereto at its upperend a head l5 which is provided with opposed, downwardly and outwardlyinclined shoulders I5, said head being provided, also, with anupstanding tubular neck portion Il which is externally screwthreaded andscrewthreadedly receives a cap I8. The head I5 of the tube I4 of thefuse cartridge Cia is provided with a rearwardly extended lug I9 (Fig.3) to which is secured a vertically disposed latching member 20, saidlatching member being secured tov said lug I3 by a screw 2l and a secondscrew 22 being provided for securing the lower portion of said latchingmember to the lower portion of the head I5. The head i5 has extendedforwardly therefrom a lug 23 which supports a horizontally disposed rod24, portions of said rod 24 extending outwardly in opposite directionsfrom said lug. Also,

a rod 25 is extended downwardly and forwardly from said head I 5..

At its lower end the tube I4 of the cartridge Ca is provided with meansfor efecting its pivotal and detachable connection with the cartridgesupporting kmember l2. This means comprises a hinge member 26 which ispivotally connected to the Iouter end of a bracket 21,A said bracket.being rigidly secured to and projects at a right angle relativev to thecartridge tube I4. The bracket 21, which is spaced upwardly from thelower end or the cartridge tube I4, is provided with a downwardlyopening recess 28 (Fig. 2) which forms a housing for a pivot pin 29, thehinge member 26 being provided with an arm 30 which extends into therecess 28 of the bracket 21 and is pivotally engaged by the pivot pin29. The hinge member 23 is provided with a forwardly extending portion23a which underlies. the lower end of the cartridge tube I4, and theopposite end of said hinge member is bifurcated and terminates inopposed, forwardly opening, hook-like portions 2321 which engage thetrunnions I3 projected from opposite side 'f aces of the head portion .I2b .of the cartridge supporting member I2.

The cartridge Ca. is provided with a fuse link 3i having a head 3.2.which is suitably seated within the upper portion of the fuse cartridgeCa and extends downwardly through the tube I4 of said cartridge, thelower portion of said fuse link extending from the open lower end of thecartridge tube and partially `embraces the forward portion 25a off thehinge member 23 and is engaged by a binding post 3.3 which is mounted onthe hinge member 26 at a side thereof (Fig. 2). Thus, un-

der normal operating conditions, the cartridge swings about the axes ofthe trunnions I3, there being no movement of the hinge member 26relative to the cartridge tube I4 because such relative movement of thehinge member is prevented by the fuse link 3 I.

Disposed at the upper end .of the fuse cartridge Ca is a housing 34which is shaped as is shown to good advantage in Figs. l, 2 and .3, saidhousing being closed by wall portions at its top, sides. and rear end,and being open at its front and bottom. rIhe housing 34 is secured to asaddle member 35 which is fixed to the upper portion of the insulator I.It will be noted by referring to Fig. 3 that a screw 33 serves as themeans for securing the housing v34 to the saddle member 35, said screw33 serving also to secure in place relative to the housing 34 a terminal31 for incoming current, and an upper contact element 38, an .upwardlyextended loop portion 39 of the upper contact element 38 and a lowerportion of said terminal 31 being interposed between the rear wall ofthe housing 34 and the saddle member 35. The shank of the screw 35passes through an opening formed through the rear wall of the housing34, through the looped portion of the contact element 38, through anopening formed through the lower portion of the terminal 31 and isscrewed into a screwthreaded opening formed in said -saddle member 35for mounting the housing 34, the upper contact element 38 and theterminal A3'! in place relative to the insulator I. Also, .a conductor33 for incoming current is mechanically and electrically connected tothe terminal 31 by .means of a suitable connector 40.

The upper contact element 38 is formed of heavy wire, or rod-likematerial, which is inherently .resilient and said contact elementincludes horizontally spaced portions which extend forwardly from thelower portion orf the loop portion 39. These horizontally spacedportions of the contact element 38 are provided with coiled portions 4Iwhich Aprovide said contact portions with additional resiliency. Also,the forward portions of said spaced contact portions are flared at theirforward portions, as is shown at 38 in Fig. l. It is to be noted thatportions of the horizontally spaced portions of the contact element 38,which are located just rearwardly of the forward, flared portions ofsaid contact element, contact with the rod 24 of the fuse cartridge Ca.Because of this arrangement an electrical path is provided whichincludes the conductor 39, the terminal 31, the contact element 38, thehead I5 of the fuse cartridge Ca, the fuse link whose head 32 contactsinternally with said cartridge head, the hinge member 26, the cartridgesupporting member I2, the bar 9, and an outgoing conductor 42 which ismechanically .and electrically connected to the bar by Asuitablesecuring means 43.

.Mounted in openings formed in the opposed side walls of the housing 34and extended transversely of said 'housing is a rod 44 (Fig. 3) on whicha. latch 45 is supported 1for rocking movement.. The latch 45 comprisesa main body portion which is provided with an opening through which therod 44 extends, and extended forwardly from said main body portion is anextension which is. provided with an inclined forward face 45a .and alatching abutment 45h which is adapted to engage the upper end portionof the 'latching member 20 that is secured to the head I5 of the fusecartridge Ca. The latch 45 has secured thereto an arm 46 which is in thevform of a flat strip of material, and said arm extends rearwardly ofthe housing 34, the weight of the combined latch and arm being sodistributed relative to the rod 44 as to Vcause -said combined structureto .normally occupy the position in which it appears m full lines inFig. 3 where the fuse cartridge Ca is locked in its effective operativeposition. By referring to Fig. 5 it will be noted that tubular spacers41 embrace the rod 44 in interposed relation with respect to the sidewalls of the housing 34 and opposite side faces of the latch 45, wherebythe latch is centered relative to the housing in a transverse direction.

The top wall of the housing 34 is provided with a short, upwardlyextended, tubular extension 4B which is received in the lower portion ofthe bore of an insulator 4.9. The insulator 49 is secured in position bya clamp 53 which embraces the lower portion of said insulator and issecured to an opstanding flange structure 5I formed on the top wall ofthe housing 34, said clamp being of conventional design and beingsecured in embracing relation with respect to the lower portion of theinsulator by a bolt and nut assembly 52 and being secured to the flangestructure 5| by a bolt and nut assembly 53. Supported by the upperportion of the insulator` 49 is a relay 54 of the no voltage type, saidrelay comprising a coil structure 55 with which is operativelyassociated an armature 56, and said coil structure being provided with asuitable frame 51.

The relay 54 includes a cylindrical housing 5B which is formed ofelectrical insulating material, said housing being provided with a topwall 59 which likewise is formed of electrical insulating material towhich the coil frame of the relay is attached by means of a suitablebracket 68. rlhe cylindrical housing 58 of the relay 54 is supported bythe upper portion of the insulator 49, the means for attaching saidcylindrical housingr to said insulator comprising a pluralityT of shoes6| which engage the circumferential face of the upper portion of theinsulator 49, said shoes being resiliently supported by spring portions62 which are substantially U-shaped, as is shown in Fig. 3. The outerportions of the U-shaped spring portions 62 are secured to the wall ofthe cylindrical housing 58 at the outer face thereof by bolt and nutassemblies 63, the lower bowed portions of said U-shaped spring portionsresting on a rib 49' of the petticoat type insulator 48.

Pivoted to the armature 56 of the relay 64 is a ceramic rod 64 whichextends downwardly through the bore of the insulator 49, the pivotalattachment of the ceramic rod 64 to the armature 56 being effected by anelement 65 which is set into a notch formed in the upper portion of therod 64 and is apertured to receive a pivot pin 66 which passes throughapertures formed through spaced portions of the armature 56 (Fig. 4).The relay structure includes a stop member 61 which preferably is formedof heavy wire, said stop member including spaced vertical portions 61a,spaced horizontal portions 61h which extend forwardly from the lowerends of said spaced vertical portions, and a bridge portion 61e whichjoins the forward ends of said spaced horizontal portions. The upper endportions of the spaced vertical portions of the stop member 61 aresecured by fastening devices 68 to a part of the frame of the coilstructure of the relay. The pivot pin 66 extends outwardly suflicientdistances beyond the spaced portions of the armature 56 so that when thearmature moves downwardly relative to the coil structure of the relay,as will presently appear herein, the opposed extended end portions ofsaid pivot pin 66 will strike the spaced horizontal portions of stopmember 61 and thereby arrest such downward movement of said armature andof the rod 64 attached thereto. The rod 64 has attached to its lowerend, by means of a screw 68', a head 68 which may be formed of metal soas to give additional weight to said rod.

By referring to Figs. 1 and 2 it will be noted that the hinge member 26has extended from its opposite sides a pair of horizontally alined pins89 which are engaged by portions of a resilient member 10. Thisresilient member is formed of heavy resilient wire, or rod material, andits lower, rear portion is in the form of a loop with spaced verticalportions 18a extended upwardly from said loop. These spaced verticalportions merge into spaced upwardly and forwardly curved portions bwhich in turn merge into downwardly and rearwardly extended portions 610c that contact with the pins 69 which are ex' tended outwardly inopposite directions from the hinge member 26.

When the fuse cartridge Ca is in the closed switch position, as is shownin Fig. 2, the pins 69 force the spaced portions 19o of the resilientmember 18 rearwardly whereby said resilient member 10 is subjected tostress that tends to rotate the hinge member 26 about the trunnions I3.However, at this time the upper portion of the fuse cartridge is latchedin the closed switch position by the latch 45 and rotation of the hingemember 26 about the trunnions I3 by the resilient member 10 isprevented.

Supported by the lower portion of the insulator 2 is a housing 1|, abracket 12 being secured to the saddle member 8 and to said housing foreffecting support of said housing 1|. The housing 1| is closed at itstop and opposite sides, and in part at its ends, said housing being openat its bottom. Pivotally attached to the forward portion of the housingby a pivot element 13 is a carriage 14, said carriage comprising opposedside walls which are joined at their upper rear ends by a rear wall 15.The carriage i4 is pron vided, also, with a Wall 16 which joins thelower portion of said opposed side walls, said wall 16 being of angularshape and being provided at its lower end with a notch 11.

At its upper rear portion the carriage 14 is provided with spaced ears18 which pivotally receive therebetween an end portion or a toggle link19, the opposite end portion of said toggle link being pivotallyattached to an end portion of a toggle arm 80. The toggle arm 88 ispivoted within the housing 1| by a pivot element 8| which is supportedat its opposite ends in openings formed in the opposed side walls ofsaid housing 1i, and said toggle arm is provided Iwith a hook-like rearend portion 82. Also, a coil spring 83 is arranged within the housing1|, the forward end of said coil spring being attached to the upper rearportion of the carriage 'Hi and the rear end of said coil spring beingattached to a spring anchoring pin 84 located within the rear portion ofthe housing 1|. It is to be noted that when the toggle arm 86 is in theposition in which it is shown by full lines in Fig. 2 the portion ofsaid arm which extends forwardly of the pivot element 8| contacts withthe lower face of the top wall of the housing 1| Also, at this time, thepivotal point of attachment of the rear portion of the toggle link 19 tothe forward end portion of the toggle arm 80 is located above a line extended between the centers of the pivotal point of attachment of theforward end portion of the toggle link 19 to the carriage 14 and thepivot element 8| of the toggle arm 86. Because oi this arrangement a settoggle is provided which prevents the coil spring 83 from drawing theupper rear portion of the carriage in a rearward direction.

The opposed side walls of the carriage are provided with alined slots 85and these slots receive opposed trunnions 86 which extend outwardly inopposite directions from the upper rear end of opposed portions 81 of acartridge-supporting member 88. These opposed portions 81 of the member88 are both shaped as is shown in Fig. 2 being spaced apart and rigidlysecured together. In other words; the opposed portions 81 of thecartridge-supporting member 68 include alined top elements 88a, andalined forward elements 88h which join said top elements, the trunnions86, previously referred to, being mounted at the rear .ends .of the topvelements '38a .and being projecting into the. slots 8.5 of the`carriage 'l-Ll..

The cartridge-supporting member 8e supports a :fuse cartridge Cb whichincludes a tube structure SQ constructed in accordancev with the tubestructure I of the cartridge Cc, as heretoforey described herein. Thetube structure 9S of the fuse cartridge Cb has xed thereto at. its lowerend a bracket .S I said bracket having a tubular portion which embracesthe lower portion of the tube structure Sii. Extended from the upperportion of the tubular portion of the bracket SEI is an arm S2 that isprovided with an enlarged end portion through which an opening isformed, said being disposed between the opposed members oi the.cartridge-supporting member .3S and being pivoted thereto by a pivotpin @3 that passes through the opening .formed through the end portionof .the arm 9.2 and is seated openings formed through said opposedportions of said cartridge-supporting member 3%. The bracket 9! isprovided, also, with a lower arm which extends from the lower Iendportion of the tubular portion thereof, said arm mi having laterallyextended extensions e which normally are seated in the notch 'il' formedat the lower portion of the angular wall 'l5 of the carriage '.Hi. Thetube `structure of the fuse cartridge Cb has xedly mounted thereon atthe upper vend thereof a head S5 having a reduced, externallyscrewthreaded neck portion Si on which a cap SS is screwthreadedlyseated, .an upper cartridge contact 99 formed of heavy wire beingsupported by lugs 99' formed on said head Sib.

The fuse cartridge 4Cb is provided with a fuse link AI @Il having a headIBI which is seated in contact with inner portions of the head S5 of thefuse cartridge Cb, said fuse link extending through the tube structureof said fuse .cartridge and bei-ng projected beyond the open lower endof said tube structure where the outer portion of said extended part ofthe fuse link is secured to a .lower portion of cartridge-supporting.member 88 by a binding post HB2. It will be noted that thecartridge-supporting member 88 includes a shoe H33 which underlies thelower end portion of the fuse cartridge for aiding in the support ofsaid fuse cartridge.

At its upper end the insulator E has fixed thereto a saddle member lill;to which a terminal E95 is. secured, said terminal having connectedthereto by a suitable connector Iiian incoming electrical conductorIll?. Also secured to the saddle member H34 and in electrical andmechanical contact with the terminal l is an upper contact H38, saidupper Contact being formed of .heavy resilient wire and being providedwith spaced portions between and in contact with which the portion. 95aof the upper cartridge contact moves when the fuse cartridge Cb isoperated to the closed switch position, as will be herein-afterexplained. The upper contact is provided with coiled portions les whichimpart resiliency to said upper contact.

The switch structure of the present invention includes a transfer rodII'i) which is supported for rotation by a lug II I formed on the topwall of the housing 'II and by a bearing element H2 secured to the bar9. At one of its ends the rod III'I is provided with a crank I I3. Atits opposite end said transfer rod .I Ill is shaped so as to be providedwith an offset portion IIA whose end portion is extended inwardly, asindicated at H5, so as to contact with the toggle arm Si! when .saidtoggle .arm is. .in the position .in which it is shown by .fulllines inFig. 2.V

The switch P which is associated with the insulator I is connected intothe preferred feeder circuit of an important user of electrical energy,while the switch E which is associated with the insulator 2 is connectedinto the emergency feeder circuit of such important electrical .energyuser, the preferred feeder .circuit .normally being in service with theswitch `P in the closed switch position, and the switch. E normallybeing in the open switch position. When the preferred feeder circutv isin service .current from said preferred `circuit energizes the coilstructure 55 ofthe relay 5e whereby the rod .5d will be held in an-elevated position. In the event, however, electrical energy ceases toflow through .the preferred feeder circuit the coil structure of therelay .56 will be deenergized thereby permitting the rod .64 to dropdownwardly and strike the arm 65 of the latch zie and move said latch tothe position vin which it is shown by dotted lines in Fig. 3 where thelatch abutment 5b will be .raised out of contact with respect to theupper portion of the latching member 2G.. The resilient .member 'l willthen rotate the hinge member 2B about the trunnions I3 so as to causethe fuse 'cartridge Ca to swing outwardly and downwardly .about saidtrunnions I3. As the fuse cartridge swings` downwardly it strikes thecrank IIS of the transfer rod l i@ so as to rotate said rod and causethe inturned portion I I5 thereof to move the toggle arm 80 upwardly.This will break the toggle provided by said toggle arm B and the togglelink 'i9 and permit the coil spring 83 to rotate the carriage 1d rapidly.about the pivot element '13 and move the fuse cartridge Cb quickly toits closed switch position where the cartridge Contact 99 contacts withthe upper contact ISS to place the emergency feeder circuit in service.

In addition to the operation described above the improved switchstructure of the present invention affords protection in the event anoverload or short circuit occurs on the primary circuit. As a result ofsuch an overload or short circuit the fuse link of the fuse cartridge Cawill be ruptured and the hinge member 26 of fuse cartridge Ca freed, atits outer or link-engaging end and acting under the forces impartedthereto, turns rapidly about the two axes defined by the trunnions i3and the pivot element 29. Movement of the hinge members about thetrunnions I3 is accompanied by an endwise lowering of the cartridge tubestructure, which when clear of the contact element 38, swings outwardlyand downwardly to the open-switch position. Here, also, the downwardswinging fuse cartridge strikes the crank I I3 of the transfer rod androtates same so as to cause the fuse cartridge Cb to be rapidly moved toits closed-switch position as has been previously explained herein.

Also, in the event an overload or short circuit occurs on the emergencycircuit while the fuse cartridge Cb is in the closed-switch position,the cartridge-supporting. member will be freed at its lower end, becauseof the ruptured fuse link. This will result in said cartridge-supportingmember swinging downwardly about the axes of the trunnions 85 with aconsequent endwise lowering of fuse cartridge so that the end portion ofthe lower arm 94 of the bracket 9! is disengaged from the notch 'Il ofthe carriage 'Ill yand the cartridge Contact 98 is freed from the uppercontact 108. The fuse cartridge then falls outwardly and downwardly toits open lswitch posi- 9 tion whereby the emergency feeder circuit iscompletely interrupted. When either the fuse cartridge Ca or the fusecartridge Cb drops out of the closed switch position as a result ofrupture of its fuse link, as described above, any arc created because ofthe rupture of the fuse link is eX- tinguished within the tube structureof the fuse cartridge by gas given off by the horn fiber within the tubestructure because of the effect of the heat of the arc on said horn ber.

The latch 45 has associated therewith means for manually actuating saidlatch when it is desired to manually cause the fuse cartridge Cc, tomove to the open-switch position. This means comprises a length of heavywire HS which is coiled about one of the spacers il that embrace the rod44 on which the latch 45 is supported (Figs. 3 and 5). A portion Ill ofsaid length of wire extends forwardly from the coiled portion H8 thereofand extends beyond the forward end of the housing 34, while anotherportion H9 of said length of wire extends rearwardly from said coiledportion I I8 and is provided with a laterally extended portion |20 whichoverlies the member 45 of the latch 45. When it is desired to manuallyunlatch the upper end of the fuse cartridge Ca the forward end portionof the length of wire IIB is elevated, as indicated by dotted lines inFig. 3, thereby causing the lateral portion i2@ of said length of wireto depress the member d of the latch and free the latch member 2Utherefrom.

I claim:

1. A switch structure comprising a switch having a fuse cartridgesupported for pivotal movement into and out of the closed-switchposition, spring means for urging said fuse cartridge toward theopen-switch position, a latch engaging and latching said fuse cartridgein the closedswitch position and means comprising a relay for actuatingsaid latch for releasing the fuse cartridge of the first-mentionedswitch for movement out of the closed-switch position on interruption ofthe flow of current through said fuse cartridge of said rst-mentionedswitch, a second switch having a fuse cartridge supported for pivotalmovement into and out of the closed-switch position and normallysupported in an openswitch position when said first fuse cartridge is inthe closed-switch position, normally inactive actuating means connectedwith said second switch, transfer means actuated by movement of the fusecartridge of the rst-mentioned switch out of the closed-switch positionto actuate said actuating means to cause the fuse cartridge of thesecond-mentioned switch to be moved into the closed-switch position,said relay including coil means which is energized by flow of currentthrough the first-mentioned fuse cartridge, and a member which is heldin an elevated position by the energized coil means of the relay andwhich is released by de-energization of said coil for latch actuatingmovement.

2. A switch structure comprising a switch having a pair of spacedterminals and having a fuse cartridge biased toward open-switch positionand supported for pivotal movement into and out of closed-switchposition relative to said spaced terminals, a fusible element associatedwith said fuse cartridge and completing a circuit through said spacedterminals in the closed-switch position of said fuse cartridge, amechanically actuated latch engaging and latching said fuse cartridge inthe closed-switch position and means for actuating said latch forreleasing the fuse cartridge of the first-mentioned switch for movementout of the closed-switch position on interruption of the flow of currentthrough said fuse cartridge of said first-mentioned switch, a secondswitch having a fuse cartridge supported for pivotal movement into andout of closedswitch position and normally supported in an open-switchposition when said first fuse cartridge is in the closed-switchposition, normally inactive actuating means connected with said secondswitch, transfer means actuated by movement of the fuse cartridge of thefirst-mentioned switch out of the closed-switch position to activatesaid actuating means to cause the fuse cartridge of the second-mentionedswitch to be moved into the closed-switch position.

3. A switch structure comprising a switch having a pair of spacedterminals and having a fuse cartridge biased toward open-switch positionand supported for pivotal movement into and out of closed-switchposition relative to said spaced terminals, a fusible element associatedwith said fuse cartridge and completing a circuit through said spacedterminals in the closed-switch position of said fuse cartridge, amechanically actuated movably supported latch engaging and latching saidfuse cartridge in the closed-switch position, and means for actuatingsaid latch for releasing the fuse cartridge of the Erst-mentioned switchfor movement out of the closed-switch position on interruption of theiiow of current through said fuse cartridge of said rst-mentionedswitch, a second switch having a fuse cartridge supported for pivotalmovement into and out of closed-switch position and normally supportedin an open-switch position when said rst fuse cartridge is in theclosed-switch position, normally inactive actuating means connected withsaid second switch, transfer means actuated by movement of the fusecartridge of the firstmentioned switch out of the closed-switch positionto actuate said actuating means to cause the fuse cartridge of thesecond-mentioned switch to be moved into the closed-switch position.

4. A switch structure comprising a switch having a pair of spacedterminals and having a fuse cartridge biased toward open switch positionand supported for pivotal movement into and out of closed-switchposition relative to said spaced terminals, a fusible element associatedwith said fuse cartridge and completing a circuit through said spacedterminals in the closed-switch positlon of the fuse cartridge, amechanically actuated pivotally supported latch engaging and latchingsaid fuse cartridge in the closed-switch position, and means for causingthe fuse cartridge of the first-mentioned switch to move out of theclosed-switch position on interruption of the ow of current through saidfuse cartridge of said first-mentioned switch, a second switch having afuse cartridge supported for pivotal movement into and out ofclosed-switch position and normally supported in an open-switch positionwhen said first fuse cartridge is in the closed-switch position,normally inactive actuating means connected with said second switch, afusible element associated with said fuse cartridge of said secondswitch, transfer means actuated by movement of the fuse cartridge of therstmentioned switch out of the closed-switch position to actuate saidactuating means to cause the fuse cartridge of second-mentioned switchto be moved into the closed-switch position, said fusible element of thefuse cartridge of the first-mentioned switch serving to release saidfuse cartridge Vfor movement out of the closed switch position onrupture `of said fusible element.

5. A switch structure comprising a switch having a pair ofspaced-terminals vand having a-fuse cartridge 'biased toward open switchposi-'tion and supported for pivotal -movement into and out ofclosed-switch `position relative to said spaced terminals, a fusibleelement yassociated. with Asaid fuse cartridge and completing -a circuitthrough said spaced Vterminals in the closed-,switch 'position of thefuse cartridge, a mechanically actuated pivotally supported latchengaging and latching said fuse cartridge in the closed-switch position,and means for causing the fuse cartridge ofthe mst-mentioned switch Ytomove vout of the closed-switch position on interruption of the flowcurrent through said -fuse cartridge of said first-mentioned switch, asecond switchhaving a fuse cartridge supported for `pivotal movementinto 'and cut of closed-,switch vposition and normally supported in anopen-switch position when said first fuse cartridge Vis in 'theclosedswitch position, normally inactive actuating means connected withsaid second switch, La fusible element associated 'with said Vfusecartridge of said second switch, transfer means actuated by movementofthe Afuse cartridge o f the iirst-mentioned switch out of theclosed-switch Cil 12 position to actuate said actuating means sto -eausethe fuse cartridge of second-mentioned switch to be moved into --theclosed-switch position, said fusible element of the`ii-rstmentionedstili-tch and said 'fusible element /of thelsecond-mentioned switch serving lto release `the fuse v'cartridges rotthe respective switches :for `movement out of Vthe closed-switchpositions on rupture of said us'ib'le elements.

ROBERT A. GESEILSCHAR References Cited in :the file :of 'this Apatent'.

UNITED STATES PATENTS Number Name Date Re. 16,917 Williams ,Mar1v27,1928 .527,501 McLaughlin Det. 16 189.4 894,333 Ledwinka ,...V ,July28, 19,08 963,728 Ayer ,July 5J 1910 A1,894,056 Pittman et al. Jan. ,10,l1933 2,059,796 Johnson Nov. .3, 1936 2,140,906 Froland .,Dec. 20 1.9382,213,164 Herault Aug. 27, 1940 2,229,531 Tornquist Jan. Y21, v1941FOREIGN PATENTS Number Country Date 360,057 Great Britain Nov. 5, 1931543,027 France r May .26, 1922

